264224-65-9

Upstream product

• 555-16-8 4-nitrobenzaldehdye 
• 67-64-1 acetone 
• 123-42-2 4-Hydroxy-4-methyl-2-pentanone 
• 147-85-3 L-proline 
• 71444-29-6 (2RS)-2-[(RS)-hydroxy-(4-nitrophenyl)methyl]cyclohexanone 
• 71444-30-9 (2SR)-2-[(SR)-hydroxy-(4-nitrophenyl)methyl]cyclohexanone 
• 619-73-8 4-nitrobenzyl chloride 
• 108-22-5 Isopropenyl acetate 
• 88958-64-9 1-(4-nitrophenyl)-1-hydroxy-3-butanone 
• 141-97-9 ethyl acetoacetate 
• 75-07-0 acetaldehyde 
• 78-93-3 butanone 

Downstream Products

• 1048378-02-4 C₁₈H₁₉N₃O₃ 
• 1356828-01-7 (1R,3R)-1-(4-nitrophenyl)-1,3-butanediol 
• 1356828-06-2 (1S,3R)-1-(4-nitrophenyl)-1,3-butanediol 
• 1204698-94-1 (1R,3S)-1-(4-nitrophenyl)-1,3-butanediol 
• 1356828-04-0 (1S,3S)-1-(4-nitrophenyl)-1,3-butanediol 

Relevant academic research and scientific papers

Highly diastereo- and enantioselective direct aldol reactions of cycloketones with aldehydes catalyzed by a trans-4-tert-butyldimethylsiloxy-l-proline amide

An organocatalyst derived from trans-4-hydroxy-l-proline and (1S,2S)-1,2-diphenyl-2-aminoethanol catalyzes the direct aldol reactions of cycloketones with a wide scope of aldehydes in high yields and with excellent diastereoselectivities of up to >99:1 an

Functional group requirements within the peptide H-Pro-Pro-Asp-NH2 as a catalyst for aldol reactions

H-Pro-Pro-Asp-NH2 1 is a versatile catalyst for asymmetric aldol reactions. In this work, the functional group tolerance within the catalyst structure has been examined. Several analogs of H-Pro-Pro-Asp-NH2 in which the N-terminal secondary amine or the carboxylic acid in the side chain of the aspartic acid residue is replaced by different functional groups were prepared. Evaluation of their catalytic properties revealed that both the N-terminal secondary amine and the carboxylic acid are important for catalysis. The implications for the reaction mechanism are discussed.

Microwave-assisted asymmetric organocatalysis. A probe for nonthermal microwave effects and the concept of simultaneous cooling

(Chemical Equation Presented) A series of five known asymmetric organocatalytic reactions was re-evaluated at elevated temperatures applying both microwave dielectric heating and conventional thermal heating in order to probe the existence of specific or nonthermal microwave effects. All transformations were conducted in a dedicated reactor setup that allowed accurate internal reaction temperature measurements using fiber-optic probes. In addition, the concept of simultaneous external cooling while irradiating with microwave power was also applied in all of the studied cases. This method allows a higher level of microwave power to be administered to the reaction mixture and, therefore, enhances any potential microwave effects while continuously removing heat. For all of the five studied (S)-proline-catalyzed asymmetric Mannich- and aldol-type reactions, the observed rate enhancements were a consequence of the increased temperatures attained by microwave dielectric heating and were not related to the presence of the microwave field. In all cases, in contrast to previous literature reports, the results obtained either with microwave irradiation or with microwave irradiation with simultaneous cooling could be reproduced by conventional heating at the same reaction temperature and time in an oil bath. No evidence for specific or nonthermal microwave effects was obtained.

Solvent-free asymmetric direct aldol reactions organocatalysed by recoverable (Sa)-binam-l-prolinamide

The combination of (Sa)-binam-l-Pro (5 mol %) and benzoic acid (10 mol %) was used as catalysts in the direct aldol reaction between different aliphatic ketones and 4-nitrobenzaldehyde under solvent-free reaction conditions. Three different pro

(S)-Histidine-based dipeptides as organic catalysts for direct asymmetric aldol reactions

The structure/activity relationships for some (S)-histidine-based dipeptide catalysts in direct aldol reactions have been examined. The reactivities and stereoselectivities are shown to be dependent upon the intramolecular cooperation of side-chain functi

Enhancing the selectivity of prolinamide organocatalysts using the mechanical bond in [2]rotaxanes

The synthesis of a pair of switchable interlocked prolinamides and their use as organocatalysts in three different enamine-activated processes are reported. A diacylaminopyridine moiety was incorporated into the thread for directing [2]rotaxane formation further allowing the association of complementary small molecules. The rotaxane-based systems were tested as organocatalysts in asymmetric enamine-mediated processes, revealing a significantly improved catalytic ability if compared with the non-interlocked thread. The presence of an electron-withdrawing nitro group at the macrocycle helps to achieve high conversions and enantioselectivities. These systems are able to interact with N-hexylthymine as a cofactor to form supramolecular catalysts displaying a divergent catalytic behaviour. The presence or absence of the cofactor controls the chemoselectivity in competitive reactions.

Proline-derived N-sulfonylcarboxamides: Readily available, highly enantioselective and versatile catalysts for direct aldol reactions

Proline catalysis of the asymmetric direct aldol reaction involves both the secondary amine function and the carboxyl group of the amino acid. N-Sulfonylcarboxamides are known to be of similar acidity as carboxylic acids, and three N-arylsulfonyl derivati

Decarboxylative aldol reaction catalysed by lipases and a protease in organic co-solvent mixtures and nearly anhydrous organic solvent media

The effects of the choice of lipase, reaction medium, immobilization, presence of additives and temperature on conversion and stereoselectivity during a lipase catalysed decarboxylative aldol reaction were examined. It was shown that Candida antarctica lipase B (CALB) catalysed a decarboxylative aldol reaction between 4-nitrobenzaldehyde and ethyl acetoacetate in a 60% acetonitrile40% aqueous buffer co-solvent mixture. Interestingly, free and immobilized forms of CALB showed opposite enantioselectivity in this media. The addition of 30 mol% imidazole increased the reaction rate from 8.5 to 55.7 μM min-1 mg-1. A 98% conversion could be achieved in 14 h (instead of 168 h) by adding imidazole. Other lipases also catalysed this reaction in different reaction media to a varying extent. With Mucor javanicus lipase in 30% DMSO, 20% enantiomeric excess (ee) of the (R)-product was observed. CALB also catalysed this reaction in nearly anhydrous acetonitrile. In the presence of cross-linked protein coated microcrystals of CALB, 90% conversion was obtained in this media in 24 h. A commercially available protease, alcalase, was also found to catalyse this reaction. While low water media gave poor conversion, the reaction in aqueous60% acetonitrile co-solvent mixture gave 99% conversion in 72 h, provided imidazole was used as an additive.

Broadening the aldolase catalytic antibody repertoire by combining reactive immunization and transition state theory: New enantio- and diastereoselectivities

Nine efficient aldolase antibodies were generated by using hapten 1. This hapten unites reactive immunization and the transition state analogue approach in a single molecule. Characterization of two of these antibodies reveals that they are highly proficient (up to 1000-fold better than any other antibody catalyst) and enantioselective catalysts for aldol and retro- aldol reactions and exhibit enantio-and diastereoselectivities opposite to that of antibody 38C2.

Sterically and electronically tunable and bifunctional organocatalysts: Design and application in asymmetric aldol reaction of cyclic ketones with aldehydes

Sterically and electronically tunable and bifunctional organocatalysts have been developed and evaluated in the direct aldol reaction of heterocyclic ketones. Catalysts with different substituents showed variable catalytic efficiency for analogous substra